The present invention relates to distributed databases and, more particularly, to the processing of data of distributed databases.
Databases are widely applied to fields like e-business, social networking, internet searching and internet of things (IOT), etc. Databases include relational database and non-relational database. In a relational database, a table is a formatted data structure. The field composition is same for all tuples in a table. Although not all fields are needed for all tuples, the database will allocate all fields for each tuple. Such a structure may facilitate operations like linking one table with another.
A non-relational database stores information with tuples consisting of key-value pairs. Its structure is not fixed and different tuples may have different fields. Each tuple may have additional key-value pairs for itself on a need basis, thus it is not limited by a fixed structure. Therefore, non-relational databases have the feature of good scalability. Because of the feature, non-relational databases have also been developed rapidly.
Both relational databases and non-relational databases may store multi-dimensional data. Examples of multi-dimensional data include measurement data of sensors, such as temperature value and wind speed value measured at different points of time. In querying database, if a particular sensor and a time recorded by the particular sensor are to be queried simultaneously, the sensor's device-id and the time constitute a two-dimensional data. If a particular sensor and a time and a temperature recorded by the particular sensor are to be queried simultaneously, the sensor's device-id, the time and the temperature constitute a three-dimensional data.
In the prior art there exist techniques for processing multi-dimensional data, including techniques of indexing, storage and querying with respect to multi-dimensional data. However, when applying these techniques to process multi-dimensional data, extra computing resources need to be consumed for higher efficiency. With the rapid increase in the amount of database data processed by various applications, it is increasingly important to mitigate the contradiction.